The use of extruded hollow bars made of aluminum or the alloys thereof as pipelines in the units for channeling and distributing gaseous or liquid fluids, such as air, gas, oils, water, etc. has already been proposed. These bars have usually at least one longitudinal hole and grooves along the sides of the perimeter defined by longitudinal beads or fins obtained from the extrusion. The bars thus shaped can be connected, in line or at an angle, with other identical hollow bars with the aid of round tubular joints, which are inserted in a fluid-tight manner into the hole of the adjacent bars and with connecting plates which are joined and are locked by means of screws in the outer grooves of the bars to be connected.
However, such a method for constructing pipelines for fluids is complex, labor-intensive, burdensome and not without disadvantages. This method involves the use of extruded hollow bars that have a relatively large and elaborate cross section given the presence of the fins or the faces which must delimit the outer grooves for anchoring the connecting plates. Thus, the bars will be relatively bulky and heavy, and given their profile, are difficult, if not impossible, to bend, where necessary, without modifying the profile of the section in the bent part. In addition, the connecting plates are also complex and require counter-plates for the locking in the outer grooves of the section.